Is it possible for a husband to be a smoker without his wife knowing?

Yes, but only if she has no sense of smell or if she smokes herself and doesn't realise that half the stench is his.

Norm Neill, Leichhardt

I attended university with a man from the country, which meant we had to attend blocks of lectures about seven times a year. Due to his work commitments, he was away from home for about half the time. He smoked cigarettes and after about nine years his wife was apparently oblivious. Then his wife made a confession and he told her about his secret.

Steve Barrett, Glenbrook

Do worms sleep?

They do ... but not quite like you and I. But they do spend long periods completely inactive. It's called "estivation". Worms do this when it's too dry for them. They just head deep in the soil, tie themselves up in a ball and estivate.

David Buley, Seaforth

Of course, worms sleep. A worm turns only when it is awake to a situation, after having been asleep.

Morris Graham, Georgetown

If you don't dust, how high will it build up?

It won't. Dust settles only on places that have been freshly dusted. The reason for this might be because it is afraid of heights.

Glen Fredericks, Warners Bay

If helping others gives you an ego boost, are your actions altruistic?

If a parent runs into a burning house to save their child, it's to save themselves from grief. In a queue, if the person in front of you drops $20 without realising it and you return it, this is to know that someone thinks well of you. If someone risks their own life to save a drowning stranger, this is because they are living up to the personal standard they have set for themselves, therefore being true to oneself.

Have you ever knowingly done the wrong thing by your own standards and regretted it, because you feel bad? So, if helping others gives you an ego boost, are you being altruistic? No, because altruism does not exist.

R. Doherty, Newcastle

What is the name of the table-cleaning utensil used in restaurants?

This waiter calls it a "crumber": to gather crumbs; my boss prefers "scraper": to clean the table top. Semantics aside, the flourish of its use is usually directed, in my case, at the wan ... sorry, I mean diners, so they remove pads of keys, mobile phones, napkins, sun glasses and especially their elbows off the table cloth. Table manners aren't what they used to be.

- Who invented vertical blinds, and can they be prosecuted for crimes against aesthetics?

- Do eyeballs grow, and if so, how much?

- Where did John and Jane Doe come from?

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